1. Field of the Invention
The present invention relates to an IC card for use, for example, in communication through a LAN and a modem.
2. Description of the Related Art
A conventional IC card will now be described with reference to FIGS. 10 to 12. A rectangular lower cover 21 formed of a metallic plate has a base portion 21a which is in the shape of a flat plate, side walls 21b formed on both sides of the base portion 21a by bending, and a rear wall 21c formed at the rear of the base portion 21a by bending.
A rectangular upper cover 22 formed of a metallic plate has a base portion 22a which is in the shape of a flat plate, side walls 22b formed on both sides of the base portion 22a by bending, a rear wall 22c formed at the rear of the base portion 22a by bending, and an arm portion 22d extending inwards from a side wall 22b.
A rectangular frame 23 formed by molding with use of a synthetic resin has frame portions 23a disposed throughout the whole periphery of the rectangular shape, a rectangular receptacle portion 23b formed as a concave portion inside the frame portions 23a, and stepped portions 23c formed in the receptacle portion 23b.
The frame 23 has a size which is almost the same as the external form of the base portion 21a of the lower cover 21, and it is placed on the base portion 21a while being received within the lower cover 21. The frame 23 is secured to the lower cover 21, for example, by bending the side walls 21b.
A substrate member 25 having a conductive pattern (not shown) and various electric components 24 attached thereto is placed on the stepped portions 23c of the frame 23 and in this state it is received in the receptacle portion 23b of the frame. The whole periphery of the substrate member 25 is established its position by the receptacle portion 23b.
The socket 26 is constituted by a female type socket forming part of a connector and it has a terminal (not shown) to be connected to a terminal (not shown) of a male connector. The socket 26 is positioned at the front portion of the frame 23 and in this state the terminal thereof is connected to the conductive pattern on the substrate member 25.
The lower cover 21 and the upper cover 22, with the substrate member 25 and the socket 26 mounted thereto, are combined together to form a case 27 having an accommodating portion 27a.
When the case 27 is formed, the frame 23, substrate member 25 and socket 26 are accommodated within the accommodating portion 27a and the arm portion 22d of the upper cover 22 comes into contact with an earth pattern of the conductive pattern.
The IC card constructed as above is inserted into and ejected from an IC card connector.
There are several types of such IC cards respectively having substrate members 25 with different electric components 24 mounted thereon. The electric components 24 are different in height, thus giving rise to the necessity that the supporting position be changed for each substrate member 25 in the vertical direction of the case 27.
According to the prior art, several types of frames 23 different in the height of stepped portions 23c are provided, whereby substrate members 25 having electric components 24 of different heights can each be accommodated in the case 23.
In the conventional IC card, since the frame 23 for supporting the substrate member 25 has a size equal to that of the base portion 21a of the lower cover 21, the frame 23 is large in size and therefore the material cost and the manufacturing cost become high. Moreover, different frames 23 are required depending on the type of IC card used, thus giving rise to the problem that the cost of IC card becomes extremely high.